<!doctype html>
<html lang="en">
<head>
	<meta charset="UTF-8">
	<title>Document</title>
	<style type="text/css">		
		/*正数第n个*/
		/*ul li:nth-child(3) {
			color: red;
		}*/
		
		/*倒数第n个*/
		/*ul li:nth-last-child(3) {
			color: green;
		}*/

		/*偶数*/
		/*ul li:nth-child(even) {
			color: green;
		}*/
		
		/*奇数*/
		/*ul li:nth-child(odd) {
			color: red;
		}*/

		ul li:nth-child(2n+1) {
			color: green;
		}
	</style>
</head>
<body>
	<ul>
		<li>这是元素1</li>
		<li>这是元素2</li>
		<li>这是元素3</li>
		<li>这是元素4</li>
		<li>这是元素5</li>
		<li>这是元素6</li>
		<li>这是元素7</li>
		<li>这是元素8</li>
		<li>这是元素9</li>
		<li>这是元素10</li>
	</ul>
</body>
</html>